JP2007116335A - Solid-state imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To exactly correct even movable smears by correctly detecting the movement of an inclined smear to be generated on an imaging surface due to a moving high-luminance subject. <P>SOLUTION: A motion detector 400 detects the relative motion of the inclined smear 204 to be generated on the imaging surface 200 of a solid-state imaging device against a reference line, and a smear position detector 500 detects the smear position in the reference line. A smear correction signal generator 600 generates the smear correcting signal, and a correcting position calculator 700 specifies the smear correcting position. An adder 702 adds smear correction data having polarity opposite to that of the smear to the data of the pixel to be corrected, and thus, the smear is suppressed. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a solid-state imaging device having a function of correcting an inclined smear that occurs on an imaging surface due to the incidence of light from a moving high-luminance subject.

  When spot light from a high-luminance object such as the sun or night car light enters the imaging surface of a camera using a solid-state image sensor (CCD, etc.), the vertical transfer charge becomes excessive. Smear (a bright vertical band on the screen) occurs. In particular, a digital camera that does not include a mechanical shutter, such as a camera mounted on a mobile phone or the like, is prone to smear, and even with a digital camera that includes a mechanical shutter, the mechanical shutter does not operate in the video shooting mode. , Smear is likely to occur.

  In order to reduce this smear, the level of the horizontal line in the optical black (optical black) area provided around the imaging surface of the solid-state imaging device (normally a black level within a predetermined range) is locally A technique has been proposed in which a protruding portion with a high level is detected, thereby obtaining smear position and smear level information, and correcting pixel data at the corresponding position in the effective pixel region (for example, Patent Document 1). reference).

  The optical black region is a region for defining a black level, and has a structure in which a photoelectric conversion element (photosensor) is covered with a light shielding film. However, when smear occurs in the effective pixel area, the same level fluctuation as the smear also occurs in the line data of the optical black area. Using this point, the smear generation position (in which line in the vertical direction the smear is generated) and the smear level are detected, and for example, a correction value of reverse polarity is applied to the pixel data of the corresponding location. By adding, smear can be reduced.

In Patent Document 1, since random noise is superimposed on the pixel data of the horizontal line in the optical black region, the data of the pixels at the same horizontal position in several adjacent lines are added and averaged, By canceling random noise, the accuracy of smear correction is improved.
JP 7-67038 A

  However, the smear correction technique described in Patent Document 1 is based on the premise that smears (high luminance vertical bands) are generated in the vertical direction, and therefore cannot be applied to cases where smears occur obliquely. That is, when a high-luminance subject that causes smear is moving at a very high speed (for example, when a headlight of an automobile traveling at high speed enters the imaging surface), the smear is on the imaging surface. It may occur with an inclination.

  The technique of Patent Document 1 is based on the premise that the position of smear that occurs in the horizontal line of the optical black area matches the position of smear that occurs in the horizontal line of the effective pixel area. However, when the smear is inclined, the position of the smear generated in the horizontal line of the optical black area is different from the position of the smear generated in each horizontal line of the effective pixel area. Therefore, based on the smear detection result in the optical black area, even if correction data with reverse polarity is added to pixels in the same horizontal position in the effective pixel area, smear cannot be canceled. May be distorted and image quality may deteriorate.

8A and 8B are diagrams for explaining a smear correction problem. FIG. 8A is a diagram illustrating an imaging surface when the smear does not move on the screen, and FIG. 8B is an imaging surface when the smear moves. FIG.
8A and 8B, the imaging surface 100 of the solid-state imaging device has an effective pixel region 102, a rear vertical optical black region OB1, and a front vertical optical black region OB2, and each imaging surface 100 includes Smears 104a and 104b, which are bright vertical bands due to light from a high-luminance subject, are generated.

  In FIG. 8A, since the smear extends in the vertical direction, the horizontal position of the smear is the same in any line, for example, the horizontal lines L1 and L2 in the figure, but in the case of (b) Since the smear is inclined, the horizontal position of the smear is different for each line. For example, in the horizontal lines L1 and L2, the smear position is shifted by an amount corresponding to the inclination angle of the smear. Therefore, in the case of (b), a smear with movement cannot be canceled accurately unless the position is shifted and corrected for each horizontal line.

  The present invention has been made in view of such circumstances, and its purpose is to accurately detect the movement of an inclined smear generated on the imaging surface due to a moving high-luminance subject, and to move the object. It is to enable accurate smear correction for smear.

The above object of the present invention is achieved by the following configuration.
(1) A solid-state imaging device that corrects, for captured image data, the effect of smear that is tilted on the imaging surface due to the incidence of light from a moving, high-luminance subject, and is configured to correct smear on a specific reference line. A smear position detection unit that detects a position and a smear position in another line separated from the reference line by a predetermined line, and a horizontal shift amount between the smear position of the reference line and the smear position of the other line, and Based on the smear motion detection unit that detects the deviation direction, the detection result of the smear position detection unit and the smear motion detection unit, and the inter-line distance between the reference line and the other line, the inclination of the smear A correction position calculation unit that calculates a correction position of each line in the effective pixel area of the imaging surface from the inclination amount; And a smear correction unit that performs correction processing on image data at the correction position in the effective pixel region.

  According to this solid-state imaging device, the smear position on the reference line is detected, and the smear position on the other lines that are separated from the reference line by a predetermined line is shifted in the horizontal direction from the smear position of the reference line. And the relative movement of the smear as seen from the reference line is detected by detecting whether the deviation occurs in the left or right direction, and the smear position information on the reference line and the relative movement of the smear are detected. Based on the information (for example, by performing a geometric operation using a right triangle), the correction position (position of the pixel to be corrected) in each of a plurality of horizontal lines in the effective pixel region is calculated and the effective By performing correction processing to reduce smear on the pixel data at the relevant part of the horizontal line in the pixel area. Te, also smear in motion, it becomes possible to carry out accurate smear correction.

(2) In the solid-state imaging device according to (1), the smear position detection unit uses a horizontal line in a vertical optical black region or a dummy region as a reference line, and is a locally high level in the reference line. 1. A solid-state imaging device, comprising: detecting a position of one portion and a position of a second portion that is locally at a high level in another line separated from the reference line by a predetermined line.

  According to this solid-state imaging device, it is possible to detect the smear movement at high speed and accurately based on the line data of the vertical optical black area or the line data of the dummy line for smear detection. It becomes possible to carry out accurate smear correction following the movement of the smear.

(3) The solid-state imaging device according to (2), wherein the smear motion detection unit uses a vertical optical black region or a dummy region in a previous frame as a reference line, and a vertical optical black region or a current frame in a current frame. A solid-state imaging device, wherein a horizontal line in a dummy area is the other line.

  According to this solid-state imaging device, when a moving high-luminance subject appears in successive frames, information on the vertical optical black region lines and dummy lines in the immediately preceding frame and information on those lines in the current frame are displayed. Both can be used to detect smear motion. There is a readout period (a period in which the charge accumulated in the photoelectric conversion element is transferred to the vertical transfer path) between the readout timing of the immediately preceding frame and the readout timing of the current frame. Thus, the substantial line interval is corrected. According to this solid-state imaging device, since the substantial line interval can be widened, the detection accuracy of the amount of motion of smear is improved.

(4) The solid-state imaging device according to any one of (1) to (3), wherein the smear correction unit uses correction data for reducing the influence of the smear as at least the correction position of the effective pixel region. A solid-state imaging device characterized by adding to the pixel data.

  According to this solid-state imaging device, it is possible to perform correction while shifting the position of each of the plurality of horizontal lines in the effective pixel region so as to follow the movement of the smear. That is, correction data having a characteristic opposite to that of smear can be added at an accurate correction position (that is, a pixel position where smear actually occurs), and therefore, smear with movement can be effectively suppressed. it can.

  According to the present invention, it is possible to accurately detect the movement of an inclined smear that occurs on the imaging surface due to a moving high-luminance subject, and to perform accurate smear correction even for a moving smear. It becomes possible.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
In the present embodiment, when an inclined smear as shown in FIG. 8B occurs when a high-luminance subject with movement is photographed, the position change of the smear is detected, and the detected smear is detected. Correction for smear reduction is performed while shifting the correction position for each horizontal line of the effective pixel area according to the amount of change.

  In the following description, “optical black” is simplified and referred to as “OB”, and “one horizontal line in the vertical optical black region” is simply referred to as “vertical OB line”. .

First, the principle for detecting smear movement will be described.
FIGS. 1A and 1B are diagrams for explaining the principle of smear motion detection, and FIG. 1A is a diagram showing another smear position on a specific reference line that is separated by m lines. The figure which shows the case where the smear position in a line has shifted | deviated to the left side, (b) is a figure which shows the case where it has shifted | deviated to the right side.

  In the present embodiment, one horizontal line in the vertical OB region or one dummy line for black level detection is defined as a reference line for smear motion detection. Here, an example in which a vertical OB line is used as a reference line will be described.

  In FIG. 1A, the Lth line in the vertical OB portion is a reference line, and the (L + M) th line separated by m lines is another line for smear motion detection. . Since the line spacing is known, if it is found that the line is separated by “m lines”, the distance between the reference line and other lines (distance in the vertical direction) is clearly specified. After that, if you know how much the smear position is shifted in the horizontal direction between both lines and whether the shift is on the left or right side, you can see in which direction the smear starts from the reference line. It is possible to specify whether the vehicle is inclined.

  The smear position on the reference line (L line) can be specified by detecting a portion (first portion) where the OB level protrudes locally and the level becomes high. In FIG. 1A, times t3 to t4 are periods in which smear occurs.

  Here, the smear can be shown as an electric pulse, and the smear width (smear pulse width) WT can be measured by counting the number of transfer clocks (read clocks) of line data. Similarly, the smear start position (PT) is measured by counting the number of transfer clocks (read clocks) from the line data read start timing (time t1) to the smear appearance timing (time t3). Can do. Thereby, the smear position in the reference line (L line) can be specified.

  The amount of horizontal smear displacement (LT) between the reference line (L line) and the other line ((L + M) line) is the appearance of positive edges G2, G1 of the smear-indicating pulses on both lines. Similarly, the timing difference can be determined by counting the number of transfer clocks (read clocks).

  Further, when the smear position (the position of the second portion) in the other line ((L + M) line) is shifted to the left side as viewed from the smear position of the reference line (L line), The positive edge G1 of the pulse indicating smear appears earlier (time t2), and the positive edge G2 of the pulse showing smear in the reference line appears later (time t3). Therefore, as shown in FIG. 1A, in the period from time t2 to time t3, the level of the pulse indicating smear in the other line is “H”, and the level of the pulse indicating smear in the reference line is “L”. is there.

  On the other hand, when the smear position of the other line ((L + M) line) is shifted to the right side as viewed from the smear position of the reference line (L line), as shown in FIG. The positive edge G2 of the pulse indicating smear appears earlier (time t5), and the positive edge G1 of the pulse showing smear in other lines appears later (time t6). Therefore, in the period from time t2 to time t3, the level of the pulse indicating smear in the other line is “L”, and the level of the pulse indicating smear in the reference line is “H”.

  Therefore, if the level of each pulse is detected in the period t2 to t3 and t5 to t6 between the time points when the positive edges G1 and G2 of the pulse indicating smear appear in both lines, the smear deviation is seen from the reference line. To see if it occurs on the right or left side.

  Thus, by detecting the appearance position PT of the pulse indicating smear and the pulse width WT on the reference line (L line), the pulse position on the reference line can be specified. Further, the detection of the amount of deviation LT in the horizontal direction of the pulse in the reference line and other lines, and the combination of the level of each pulse in the periods t2 to t3 and t5 to t6 sandwiched between the positive edges G1 and G2 of each pulse are detected. As a result, it is possible to specify the smear inclination direction, that is, the arrow R1 in FIG. 1A and the arrow R2 in FIG.

Next, calculation of the correction position of each line in the effective pixel area will be described.
FIG. 2 is a diagram for explaining a method for calculating the correction position of each line in the effective pixel region.
The imaging surface 200 of the solid-state imaging device has an effective pixel area 202 and an optical black area OB1. Here, the L line in OB1 is the reference line described in FIG. 1, and the (L + M) line is another line. L1 to L5 indicate horizontal lines in the effective pixel region 202.

  As shown in FIG. 2, there are, for example, four horizontal lines in the rear optical black region (OB1). The L line is used as a reference line, and the (L + M) line is used as another line. As described with reference to FIG. 1, by detecting each value of the smear start position PT, the smear width WT, the smear horizontal shift amount LT, and the smear shift left and right, The amount of inclination can be known.

  Then, starting from the positive edge of the reference line (L line), a line segment Q3 is drawn in the smear inclination direction, and the line segment Q3 intersects with each horizontal line L1 to L5 in the effective pixel region (S1 to S1). S5) is a starting point of smear correction in each horizontal line.

  Similarly, starting from the negative edge (falling position) of the reference line (L line), a line segment Q4 is drawn in the direction of smear inclination, and the line segment Q4 corresponds to each horizontal line L1 to L1 in the effective pixel region. Points (E1 to E5) intersecting with L5 are the end points of smear correction in each horizontal line. That is, in each horizontal line, a pixel between the smear correction start point (S1 to S5) and the smear correction end point (E1 to E5) is a smear generation region and is a target pixel for smear correction. .

  Thus, the correction position (correction target pixel) in each horizontal line in the effective pixel region 202 can be calculated by a simple geometric operation.

  Next, each value of the smear start position PT on the reference line, the pulse width WT indicating smear on the reference line, and the horizontal deviation amount LT of the smear on the reference line and other lines, which are necessary to perform smear correction, Next, a description will be given of a circuit configuration for generating a left / right deviation detection signal and a correction value (smear correction signal) for correcting smear.

  FIG. 3 is a block diagram showing a principle configuration as an example of a circuit configuration for generating data and a correction signal necessary for performing smear correction. In FIG. 3, the same reference numerals are given to the portions common to FIG.

  Reference numeral 206 denotes a high-brightness subject that moves at high speed, and the spot light from the high-brightness subject 206 generates a smear 204 that is a bright vertical band on the imaging surface 200 of the solid-state imaging device. The smear 204 is formed to be inclined on the imaging surface 200 due to the high brightness subject 206 moving at high speed.

  In the circuit of FIG. 3, at least two horizontal lines (one is a “reference line”) separated by a predetermined distance from the front optical black region OB2 and the rear optical black region OB1 provided at the front end and rear end of the imaging surface. The other data is “other line” for detecting smear motion), and basic data and correction signals necessary for smear correction are generated.

  3 includes a horizontal CCD (HCCD) 208 that horizontally transfers line data, an output amplifier 210, an A / D converter 212, and an averaging process for canceling random noise superimposed on the line data. , An extraction circuit 300 for extracting a smeared portion from the line data, a smear motion detection unit 400 for detecting smear motion, and a smear for detecting a smear position on the reference line The position detection circuit 500 includes a clock input terminal 503 for inputting a transfer clock (reading clock) CK, and a smear correction signal generation unit 600 that generates a smear correction signal J.

  The averaging unit 250 divides by an addition unit 213 that adds pixel data of a plurality of lines at the same horizontal position, a line memory 215 that temporarily stores the added data, and the number of added lines. And an averaging processing unit 217 for averaging the pixel data. The extraction circuit 300 includes a reference voltage source Vref for generating a threshold voltage and a comparator OP, and has a function of extracting a portion protruding beyond the threshold. The smear motion detection unit 400 includes a switch SW, line memories LM2 and LM3, a counter 402, and AND gates AND1 and AND2. The smear position detection circuit 500 includes counters 502 and 504. The smear correction signal generation unit 600 includes a level adjustment unit 550 and an inverter INV.

  In the line memories LM1 and LM2 of the smear motion detection unit 400, averaged line data corresponding to “reference line” and “other lines” is temporarily stored.

  The counter 402 starts counting the transfer clock (read clock) CK at the positive edge input first in the line data stored in the line memories LM2 and LM3, and at the positive edge input thereafter. , End the count. The count value output at this time is data indicating the horizontal displacement (LT) of the smear position in the “reference line” and the “other lines”.

  The two AND gates AND1 and AND2 are AND gates having an inverter arranged at one of the input terminals. When the output pulse Q1 is output from the AND gate AND1, the "reference line" to the "other line" If the smear is shifted to the left side and the output pulse Q2 is output from the AND gate AND2, the smear is shifted to the right side when viewing the "other line" from the "reference line". Yes.

  This point will be described with reference to FIG. FIGS. 4A and 4B are timing charts showing how signals Q1 and Q2 indicating whether the smear is shifted to the left or right are generated. FIG. 4A is a waveform diagram in the case where the smear is shifted to the left side when viewing the “other line” from the “reference line”, and FIG. A waveform diagram in the case where the smear is shifted to the right side when the line is viewed is shown. In the figure, LMS2 is line data of “other line” stored in the line memory LM2, and LMS3 is line data of “reference line” stored in the line memory LM3. Q1 and Q2 are detection pulses (signals indicating whether the smear is shifted to the left or the right) output from the AND gates AND1 and AND2, respectively.

  As shown in FIG. 4A, when the smear is shifted to the left side as seen from the “reference line” to the “other line”, the LMS2 is at the “H” level during the period of time t10 to t11. Thus, the LMS3 becomes “L” level, and as a result, the pulse Q1 is output. On the other hand, as shown in FIG. 4B, when the smear is shifted to the right side when the “other line” is viewed from the “reference line”, the LMS2 is set to “L” during the period of time t10 to t11. "L" and LMS3 becomes "H" level. As a result, pulse Q2 is output.

  Further, the counter 502 in the smear position detection unit 500 of FIG. 3 is connected to the output terminal of the line memory LM3 that accumulates the line data of the reference line, and starts counting together with the input of the transfer clock CK. When the positive edge is output from LM3, the count is finished. This count value becomes a signal PT indicating the smear start position in the reference line.

  The counter 504 counts the number of transfer clocks CK from when the positive edge is output from the line memory LM3 to when the negative edge is output. This count value becomes the detected value W of the pulse width of the pulse indicating smear in the reference line.

  Further, the level adjustment unit 550 in the smear correction signal generation unit 600 of FIG. 4 optimizes the amplitude (value) of the correction signal by performing peak limit processing, coefficient calculation, and the like based on the output signal of the comparator OP. The smear correction signal J is generated by inverting and outputting the polarity by the inverter INV.

  As described above, the data and correction signal necessary for performing smear correction can be generated by the circuit of FIG.

Next, the overall configuration of the solid-state imaging device having a function of detecting and correcting smear movement will be described.
FIG. 5 is a diagram illustrating an overall configuration of a solid-state imaging device having a function of detecting and correcting smear movement. In FIG. 5, the same reference numerals are given to portions common to FIG. 4.

  The solid-state imaging device of FIG. 5 further includes a correction position calculation unit 700, an AND gate AND3, and an adder 702 (functioning as a smear correction unit that performs smear correction) added to the circuit of FIG. It is configured.

  The correction position calculation unit 700 is based on the LT, Q1, and Q2 data output from the motion detection unit 400 and the PT and W data output from the smear position detection unit 500, and the method described in FIG. Thus, the correction position in each horizontal line in the effective pixel region 202 is calculated.

  When the transfer of the pixel data is started, the transfer clock CK is counted, and the correction instruction signal F1 is set to “L” at the timing when the pixel data to be corrected in the effective pixel region 202 is output from the averaging processing unit 250. "" To "H".

  When the correction instruction signal F1 becomes the “H” level, the smear correction signal (correction data having a level opposite to that of smear) J output from the smear correction signal generation unit 600 is output from the AND gate AND3. Output as is. Here, the smear correction signal output from the AND gate AND3 is F3.

  The smear correction signal F3 is added to the correction target pixel data output from the averaging processing unit 250 in the adder 702, thereby obtaining corrected pixel data in which the smear is canceled.

  In the above description, the smear movement and smear position are detected using line data in the optical black (OB) area, but are detected using line data such as a dummy line provided on the outermost periphery of the OB portion. May be.

  In addition, the averaging process in the averaging unit 250 has the effect of offsetting random noise superimposed on the line data and improving the accuracy of smear correction.

(Second Embodiment)
In this embodiment, when detecting a smear movement in real time, if a moving high-luminance subject appears in a continuous frame, information on the vertical optical black area line or dummy line in the immediately preceding frame, and the current An example of performing smear motion detection using both of the information of these lines in the frame will be described.

  It is also possible to detect smear movement in real time using multiple lines of vertical optical black area lines and dummy lines without using multiple frame memories. Since the time width is short, the amount of smear movement is very small, and the accuracy of motion detection may be reduced.

  Therefore, in the present embodiment, when a moving high-luminance subject appears in successive frames, information on the lines and dummy lines in the vertical optical black area in the previous frame and information on those lines in the current frame are displayed. Both were used to detect smear motion.

FIG. 6 illustrates a smear correction process in the case of performing smear motion detection using both the information of the lines and dummy lines in the vertical optical black area in the immediately preceding frame and the information of those lines in the current frame. FIG.
In FIG. 6, a moving high-intensity subject 206 appears in both the immediately preceding frame 200a and the current frame 200b, and as a result, smear 204 occurs continuously in both frames.

  It is assumed that smear correction is performed for the current frame 200b. At this time, it is also possible to obtain data and smear correction data necessary for smear correction using only the line data of OB1 in the current frame 200b. However, since the time between each line is short, the correction accuracy decreases.

  Therefore, the OB2 line data in the immediately preceding frame 200a is also used together to obtain data necessary for smear correction and smear correction data. Thereby, since a substantial line interval can be taken, the detection accuracy of the amount of motion of smear is improved, and as a result, the accuracy of smear correction is improved.

  However, since there is a readout period (a period in which the charge accumulated in the photoelectric conversion elements is transferred to the vertical transfer path) XT between the readout timing of the immediately preceding frame 200a and the readout timing of the current frame 200b, Considering the readout period XT, the substantial line interval is corrected.

That is, the line interval between the “reference line” in OB2 of the immediately preceding frame 200a and the “other line” in OB1 of the current frame 200b is corrected as follows.
(Line interval) = actual line interval + line interval corresponding to the number of lines corresponding to the read interval XT

  In this way, the detection accuracy of the amount of smear movement (the accuracy of smear correction) can be improved by widening the substantial line interval.

Next, a filtering correction process for correcting the pixel signal in the effective pixel area with respect to the smear movement detected by each of the above embodiments will be described.
FIG. 7 is a diagram illustrating a main configuration of a solid-state imaging device that performs a filtering process as a correction process for reducing smear. In FIG. 7, the same reference numerals are given to the portions common to the above-mentioned drawings.

  The main configuration for smear correction in the solid-state imaging device of FIG. 7 is almost the same as that of the solid-state imaging device of FIG. 5, but in the solid-state imaging device of FIG. Since filtering processing (interpolation processing, averaging processing, etc.) is performed using data, the portion for performing the filtering processing is different.

That is, in the solid-state imaging device of FIG. 7, a line memory 704 and a filtering processing unit 800 are provided in order to perform filtering processing.
Similar to the solid-state imaging device of FIG. 5, the correction position calculation unit 700 outputs a signal F <b> 1 that specifies a pixel to be corrected. Upon receiving the signal F1, the filtering processing unit 800 uses the smear correction signal obtained in each of the above-described embodiments, among the data output from the line memory 704, to perform interpolation calculation or addition based on a predetermined interpolation calculation formula. Averaging processing is performed. As a result, the smear becomes inconspicuous and the smear can be reduced.

  As described above, according to the present invention, it is possible to accurately detect the movement of the inclined smear generated on the imaging surface due to the moving high-luminance subject, and thus it is possible to accurately detect the moving smear. It becomes possible to perform accurate smear correction.

(A), (b) is a figure for demonstrating the principle of a smear motion detection, respectively, (a) is the smear position in the other line which is only m lines away from the smear position in a reference line. The figure which shows the case where has shifted | deviated to the left side, (b) is a figure which shows the case where it has shifted | deviated to the right side. It is a figure for demonstrating the calculation method of the correction position of each line in an effective pixel area | region. It is a block diagram which shows the principle structure as an example of the circuit structure for producing | generating the data required in order to perform smear correction | amendment, and a correction signal. (A), (b) is a wave form diagram which shows a mode that signals Q1 and Q2 which show whether smear has shifted to right and left, respectively, (a) is "other lines" from "reference line" (B) is a waveform diagram when smear is shifted to the left side when looking at “line”, and (b) is when smear is shifted to the right side when looking at “other line” from “reference line” It is a timing chart in the case. It is a figure which shows the whole structure of the solid-state imaging device which has a function which detects and correct | amends a motion of smear. It is a figure for demonstrating the smear correction | amendment process in the case of performing a smear motion detection using both the information of the line of the vertical optical black area | region in the immediately previous flame | frame, the information of the dummy line, and the information of those lines in the present flame | frame. is there. It is a figure which shows the principal part structure of the solid-state imaging device which performs a filtering process as a correction process for reducing a smear. It is a figure for demonstrating the subject of a smear correction | amendment, (a) is a figure which shows the imaging surface when a smear does not move on a screen, (b) shows an imaging surface when a smear has a motion FIG.

Explanation of symbols

200 Imaging surface of solid-state imaging device 204 Smear 206 High-brightness object moving at high speed OB1 Front vertical optical black area OB2, Rear vertical optical black area 208 Horizontal CCD (HCCD)
210 Output Amplifier 212 A / D Converter 213 Adder 215 Line Memory 217 Averaging Processor 250 Averaging Unit 300 Smear Extraction Circuit Vref Reference Voltage Source for Threshold Voltage Generation OP Comparator 400 Smear Motion Detector SW Switch LM2, LM3 Line memory 402 Counter AND1-AND3 AND gate (AND circuit)
500 Smear position detection circuit 502, 504 Counter 503 Transfer clock (read clock) input terminal 550 Level adjustment unit 600 Smear correction signal generation unit 700 Correction position calculation unit 702 Adder (corresponding to a smear correction unit that adds smear correction data)
704 Line memory 800 Filtering process INV Inverter F1 Correction instruction signal (specification signal of pixel to be corrected)

Claims (4)

A solid-state imaging device that corrects the influence of smear generated by tilting on the imaging surface due to the incidence of light from a moving, high-luminance subject, with respect to the captured image data,
A smear position detection unit that detects a smear position on a specific reference line and a smear position on another line separated from the reference line by a predetermined line;
A smear motion detection unit for detecting a horizontal shift amount and a shift direction between the smear position of the reference line and the smear position of the other line;
Based on the detection result of the smear position detection unit and the smear motion detection unit and the inter-line distance between the reference line and the other line, an inclination amount of the smear is obtained, and the imaging surface A correction position calculation unit for calculating the correction position of each line in the effective pixel region;
A smear correction unit that performs correction processing on image data at the correction position in the effective pixel region;
A solid-state imaging device. The solid-state imaging device according to claim 1,
The smear position detection unit uses a horizontal line in a vertical optical black area or a dummy area as a reference line, and is separated from the reference line by a predetermined line from the position of the first portion at a locally high level in the reference line. A solid-state imaging device that detects a position of a second portion that is locally high in another line. The solid-state imaging device according to claim 2,
The smear motion detection unit uses a horizontal line in a vertical optical black area or a dummy area in a previous frame as a reference line, and a horizontal line in a vertical optical black area or a dummy area in a current frame as the other line. A solid-state imaging device. The solid-state imaging device according to any one of claims 1 to 3,
The smear correction unit adds correction data for reducing the effect of smear to at least pixel data at the correction position in the effective pixel region.

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